What is the recommended treatment regimen for an otherwise healthy adult with acute herpes zoster?

Treatment Regimen for Herpes Zoster

For an otherwise healthy adult with acute herpes zoster, initiate oral valacyclovir 1 gram three times daily for 7 days, starting within 72 hours of rash onset, and continue treatment until all lesions have completely scabbed. 1, 2

First-Line Oral Antiviral Therapy

• Valacyclovir 1 gram orally three times daily for 7 days is the recommended first-line treatment for uncomplicated herpes zoster in immunocompetent adults. 1, 2, 3

• Alternative option: Acyclovir 800 mg orally five times daily for 7-10 days if valacyclovir is unavailable or not tolerated. 1, 2

• Alternative option: Famciclovir 500 mg orally three times daily for 7 days offers comparable efficacy with less frequent dosing than acyclovir. 1, 4

• Treatment must be initiated within 72 hours of rash onset to achieve optimal efficacy in reducing acute pain, accelerating lesion healing, and preventing postherpetic neuralgia. 1, 5

• Continue antiviral therapy until all lesions have completely scabbed, not just for an arbitrary 7-day period—this is the key clinical endpoint. 1, 2

When to Escalate to Intravenous Therapy

• Switch to intravenous acyclovir 10 mg/kg every 8 hours for disseminated herpes zoster (≥3 dermatomes, visceral involvement, or hemorrhagic lesions), severe immunosuppression, CNS complications (encephalitis, meningitis), or complicated ocular/facial disease. 1, 2

• Continue IV therapy for a minimum of 7-10 days and until clinical resolution is attained, then switch to oral therapy once clinical improvement occurs. 1, 2

• Monitor renal function at initiation and once or twice weekly during IV acyclovir therapy, with mandatory dose adjustments for renal impairment to prevent nephrotoxicity. 1

Pain Management During Acute Phase

• Gabapentin is the first-line oral agent for acute neuropathic pain due to herpes zoster, titrated in divided doses up to 2400 mg per day. 1

• Over-the-counter analgesics such as acetaminophen and ibuprofen are recommended to relieve acute pain in otherwise healthy adults. 1

• Topical anesthetics provide minimal benefit and are not recommended as primary therapy for acute zoster pain management. 1

Critical Treatment Caveats

• Topical antiviral therapy is substantially less effective than systemic therapy and is not recommended. 1, 2

• Do not use corticosteroid creams on active shingles lesions, as this can increase the risk of severe disease and dissemination, particularly in immunocompromised patients. 1

• Ensure adequate hydration during systemic acyclovir or valacyclovir therapy to reduce the risk of crystalluria and acyclovir-induced nephropathy. 1

• If lesions fail to begin resolving within 7-10 days, suspect acyclovir resistance and obtain viral culture with susceptibility testing; switch to foscarnet 40 mg/kg IV every 8 hours for confirmed resistance. 1, 2

Infection Control Measures

• Patients with herpes zoster should avoid contact with susceptible individuals until all lesions have crusted, as lesions are contagious to individuals who have not had chickenpox or vaccination. 1

• Cover lesions with clothing or dressings to minimize transmission risk. 1

Prevention of Future Episodes

• The recombinant zoster vaccine (Shingrix) is strongly recommended for all adults aged 50 years and older, regardless of prior herpes zoster episodes, providing >90% efficacy in preventing future recurrences. 1, 2

• Vaccination should be administered after recovery from the current episode to prevent future episodes of shingles. 1, 2